 /*******************************************************************************
  * Copyright (c) 2000, 2007 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.registry;

 import java.util.ArrayList ;
 import java.util.Arrays ;
 import java.util.List ;

 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IConfigurationElement;
 import org.eclipse.core.runtime.IExtension;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.jface.resource.ImageDescriptor;
 import org.eclipse.ui.IPluginContribution;
 import org.eclipse.ui.IWorkingSetElementAdapter;
 import org.eclipse.ui.IWorkingSetUpdater;
 import org.eclipse.ui.dialogs.IWorkingSetPage;
 import org.eclipse.ui.internal.WorkbenchPlugin;
 import org.eclipse.ui.plugin.AbstractUIPlugin;

 /**
  * A working set descriptor stores the plugin registry data for
  * a working set page extension.
  *
  * @since 2.0
  */
 public class WorkingSetDescriptor implements IPluginContribution {
     private String id;

     private String name;

     private String icon;

     private String pageClassName;
     
     private String updaterClassName;

     private IConfigurationElement configElement;
     
     private String [] classTypes;

     private String [] adapterTypes;

     private static final String ATT_ID = "id"; //$NON-NLS-1$

     private static final String ATT_NAME = "name"; //$NON-NLS-1$

     private static final String ATT_ICON = "icon"; //$NON-NLS-1$

     private static final String ATT_PAGE_CLASS = "pageClass"; //$NON-NLS-1$

     private static final String ATT_UPDATER_CLASS = "updaterClass"; //$NON-NLS-1$

     private static final String ATT_ELEMENT_ADAPTER_CLASS = "elementAdapterClass"; //$NON-NLS-1$

     private static final String TAG_APPLICABLE_TYPE = "applicableType"; //$NON-NLS-1$

     /**
      * Creates a descriptor from a configuration element.
      *
      * @param configElement configuration element to create a descriptor from
      */
     public WorkingSetDescriptor(IConfigurationElement configElement)
             throws CoreException {
         super();
         this.configElement = configElement;
         id = configElement.getAttribute(ATT_ID);
         name = configElement.getAttribute(ATT_NAME);
         icon = configElement.getAttribute(ATT_ICON);
         pageClassName = configElement.getAttribute(ATT_PAGE_CLASS);
         updaterClassName = configElement.getAttribute(ATT_UPDATER_CLASS);

         if (name == null) {
             throw new CoreException(new Status(IStatus.ERROR,
                     WorkbenchPlugin.PI_WORKBENCH, 0,
                     "Invalid extension (missing class name): " + id, //$NON-NLS-1$
 null));
         }
         
         IConfigurationElement[] containsChildren = configElement
                 .getChildren(TAG_APPLICABLE_TYPE);
         if (containsChildren.length > 0) {
             List byClassList = new ArrayList (containsChildren.length);
             List byAdapterList = new ArrayList (containsChildren.length);
             for (int i = 0; i < containsChildren.length; i++) {
                 IConfigurationElement child = containsChildren[i];
                 String className = child
                         .getAttribute(IWorkbenchRegistryConstants.ATT_CLASS);
                 if (className != null)
                     byClassList.add(className);
                 if ("true".equals(child.getAttribute(IWorkbenchRegistryConstants.ATT_ADAPTABLE))) //$NON-NLS-1$
 byAdapterList.add(className);
             }
             if (!byClassList.isEmpty()) {
                 classTypes = (String []) byClassList.toArray(new String [byClassList
                         .size()]);
                 Arrays.sort(classTypes);
             }
             
             if (!byAdapterList.isEmpty()) {
                 adapterTypes = (String []) byAdapterList.toArray(new String [byAdapterList
                         .size()]);
                 Arrays.sort(adapterTypes);
             }
         }
     }
     
     /**
      * Returns the name space that declares this working set.
      *
      * @return the name space declaring this working set
      */
     public String getDeclaringNamespace() {
         return configElement.getNamespace();
     }
     
     /**
      * Return the namespace that contains the class referenced by the
      * updaterClass. May be the bundle that declared this extension or another
      * bundle that contains the referenced class.
      *
      * @return the namespace
      * @since 3.3
      */
     public String getUpdaterNamespace() {
         return WorkbenchPlugin.getBundleForExecutableExtension(configElement,
                 ATT_UPDATER_CLASS).getSymbolicName();
     }
     
     /**
      * Return the namespace that contains the class referenced by the
      * elementAdapterClass. May be the bundle that declared this extension or
      * another bundle that contains the referenced class.
      *
      * @return the namespace
      * @since 3.3
      */
     public String getElementAdapterNamespace() {
         return WorkbenchPlugin.getBundleForExecutableExtension(configElement,
                 ATT_UPDATER_CLASS).getSymbolicName();
     }

     /**
      * Creates a working set page from this extension descriptor.
      *
      * @return a working set page created from this extension descriptor.
      */
     public IWorkingSetPage createWorkingSetPage() {
         Object page = null;

         if (pageClassName != null) {
             try {
                 page = WorkbenchPlugin.createExtension(configElement,
                         ATT_PAGE_CLASS);
             } catch (CoreException exception) {
                 WorkbenchPlugin.log("Unable to create working set page: " + //$NON-NLS-1$
 pageClassName, exception.getStatus());
             }
         }
         return (IWorkingSetPage) page;
     }

     /**
      * Returns the page's icon
      *
      * @return the page's icon
      */
     public ImageDescriptor getIcon() {
         if (icon == null) {
             return null;
         }

         IExtension extension = configElement.getDeclaringExtension();
         String extendingPluginId = extension.getNamespace();
         return AbstractUIPlugin.imageDescriptorFromPlugin(extendingPluginId,
                 icon);
     }

     /**
      * Returns the working set page id.
      *
      * @return the working set page id.
      */
     public String getId() {
         return id;
     }

     /**
      * Returns the working set page class name
      *
      * @return the working set page class name or <code>null</code> if
      * no page class name has been provided by the extension
      */
     public String getPageClassName() {
         return pageClassName;
     }

     /**
      * Returns the name of the working set element type the
      * page works with.
      *
      * @return the working set element type name
      */
     public String getName() {
         return name;
     }
     
     /**
      * Returns the working set updater class name
      *
      * @return the working set updater class name or <code>null</code> if
      * no updater class name has been provided by the extension
      */
     public String getUpdaterClassName() {
         return updaterClassName;
     }
     
     /**
      * Creates a working set element adapter.
      *
      * @return the element adapter or <code>null</code> if no adapter has been
      * declared
      */
     public IWorkingSetElementAdapter createWorkingSetElementAdapter() {
         if (!WorkbenchPlugin.hasExecutableExtension(configElement, ATT_ELEMENT_ADAPTER_CLASS))
             return null;
         IWorkingSetElementAdapter result = null;
         try {
             result = (IWorkingSetElementAdapter) WorkbenchPlugin
                     .createExtension(configElement, ATT_ELEMENT_ADAPTER_CLASS);
         } catch (CoreException exception) {
             WorkbenchPlugin.log("Unable to create working set element adapter: " + //$NON-NLS-1$
 result, exception.getStatus());
         }
         return result;
     }
     
     /**
      * Creates a working set updater.
      *
      * @return the working set updater or <code>null</code> if no updater has
      * been declared
      */
     public IWorkingSetUpdater createWorkingSetUpdater() {
         if (updaterClassName == null) {
             return null;
         }
         IWorkingSetUpdater result = null;
         try {
             result = (IWorkingSetUpdater)WorkbenchPlugin.createExtension(configElement, ATT_UPDATER_CLASS);
         } catch (CoreException exception) {
             WorkbenchPlugin.log("Unable to create working set updater: " + //$NON-NLS-1$
 updaterClassName, exception.getStatus());
         }
         return result;
     }
     
     public boolean isUpdaterClassLoaded() {
         return WorkbenchPlugin.isBundleLoadedForExecutableExtension(configElement, ATT_UPDATER_CLASS);
     }
     
     public boolean isElementAdapterClassLoaded() {
         return WorkbenchPlugin.isBundleLoadedForExecutableExtension(configElement, ATT_ELEMENT_ADAPTER_CLASS);
     }
     
     /**
      * Returns whether working sets based on this descriptor are editable.
      *
      * @return <code>true</code> if working sets based on this descriptor are editable; otherwise
      * <code>false</code>
      *
      * @since 3.1
      */
     public boolean isEditable() {
         return getPageClassName() != null;
     }

     public String getLocalId() {
         return getId();
     }

     public String getPluginId() {
         return getDeclaringNamespace();
     }
     
     /**
      * Return the config element for this descriptor.
      *
      * @return the config element
      * @since 3.3
      */
     public IConfigurationElement getConfigurationElement() {
         return configElement;
     }
 }

